Bahu M, Knight B P, Weiss R, Hahn S J, Goyal R, Daoud E G, Man K C, Morady F, Strickberger S A
Division of Cardiology, University of Michigan Medical Center, Ann Arbor 48109-0022, USA.
J Interv Card Electrophysiol. 1998 Mar;2(1):41-5. doi: 10.1023/a:1009760706944.
A variety of factors, including the number of defibrillation electrodes and shocking capacitance, may influence the defibrillation efficacy of an implantable defibrillator system. Therefore, the purpose of this study was to compare the defibrillation energy requirement using a 125 uF two-electrode defibrillation system and a 90 uF three-electrode defibrillation system.
The defibrillation energy requirements measured with both systems were compared in 26 consecutive patients. The two-electrode system used a single transvenous lead with two defibrillation coils in conjunction with a biphasic waveform from a 125 uF capacitor. The three-electrode system used the same transvenous lead, utilized a pectoral implantable defibrillator generator shell as a third electrode, and delivered the identical biphasic waveform from a 90 uF capacitor. The two-electrode system was associated with a higher defibrillation energy requirement (10.8 +/- 5.5 J) than was the three-electrode system (8.9 +/- 6.7 J, p < 0.05), however, the leading edge voltage was not significantly different between systems (361 +/- 103 V vs. 397 +/- 123 V, P = 0.07). The two-electrode system also had a higher shocking resistance (49.0 +/- 9.0 ohms vs. 41.4 +/- 7.3 ohms, p < 0.001) and a lower peak current (7.7 +/- 2.6 A vs. 10.1 +/- 3.7 A, p < 0.001) than the three-electrode system.
A three-electrode defibrillation system that utilizes a dual coil transvenous lead and a subcutaneous pectoral electrode with lower capacitance is associated with a lower defibrillation energy requirement than is a dual coil defibrillation system with higher capacitance. This finding suggests that the utilization of a pectoral generator as a defibrillation electrode in conjunction with smaller capacitors is a more effective defibrillation system and may allow for additional miniaturization of implantable defibrillators.
多种因素,包括除颤电极数量和电击电容,可能会影响植入式除颤器系统的除颤效果。因此,本研究的目的是比较使用125微法双电极除颤系统和90微法三电极除颤系统时的除颤能量需求。
对连续26例患者使用两种系统测量的除颤能量需求进行比较。双电极系统使用带有两个除颤线圈的单根经静脉导线,并结合来自125微法电容器的双相波形。三电极系统使用相同的经静脉导线,将胸壁植入式除颤器发生器外壳用作第三电极,并从90微法电容器输送相同的双相波形。双电极系统的除颤能量需求(10.8±5.5焦耳)高于三电极系统(8.9±6.7焦耳,p<0.05),然而,系统之间的前沿电压无显著差异(361±103伏对397±123伏,P = 0.07)。双电极系统的电击电阻也高于三电极系统(49.0±9.0欧姆对41.4±7.3欧姆,p<0.001),且峰值电流较低(7.7±2.6安对10.1±3.7安,p<0.001)。
使用双线圈经静脉导线和较低电容的胸壁皮下电极的三电极除颤系统,与具有较高电容 的双线圈除颤系统相比,除颤能量需求更低。这一发现表明,将胸壁发生器用作除颤电极并结合较小的电容器是一种更有效的除颤系统,可能会使植入式除颤器进一步小型化。